1. Field of the Invention
The present invention relates to work implements and to apparatuses for positioning work implements in the agricultural and construction fields, and more particularly to increasing the effective width of work implements and to increasing the effective width which apparatuses for positioning work implements deploy those work implements.
2. Description of the Related Art
Positionable work implements useful for performing a variety of tasks, for example tasks associated with the processing of crops in a field, have long been known. An exemplary positionable work implement is disclosed in U.S. Pat. No. 4,932,197 to Allen. The Allen work implement is useful as a hay rake and is capable of being positioned in work and travel positions for performing a variety of tasks. While various designs for positionable work implements have been used with varying success, they all possess certain shortcomings which constitute the motivation for the present invention. More particularly, the effective working widths of all of the known work implements are more or less limited. Limitations to the effective working widths of these known positionable work implements limit their speed and efficiency at performing their designated tasks.
In the production of hay (or haying), for example, the limitation to the effective working width of hay rakes also limits the speed and efficiency of hay rakes in processing crops. An increase in speed and efficiency of hay rakes is needed to more cost effectively produce hay.
Haying involves the conversion of alfalfa, clover, birdsfoot, oats, grasses, and other crops into a form suitable for long-term storage. A first step in haying is to mow the crop. A swather or windrower mows the green plants along an operator directed path, often circular or back-and-forth, cutting swaths across a field. If a windrower is used, the windrower deposits the cut green plants in a continuous, narrow row called a windrow. If a swather is used, the cut green plants fall evenly behind the swather, and a raking step follows to gather the plants into windrows.
The cut green plants most often require drying before they can be stored for an extended period of time. The windrows are thus left in the field for one or more days to dry the plants. The top layer of the windrow generally dries most readily due to maximum exposure to light and air. The bottom layer and the interior of the windrow are more insulated from light and air and thus do not dry as readily as the top layer. In order to more quickly dry all of the cut plants in the windrow, an over-turning operation can be performed. A hay rake can be used to overturn the windrows to expose the green, wet cut plants underneath to light and air for drying. Over-turning may be performed once or several times until the windrow is sufficiently dry and prepared for storage. When the cut plants are sufficiently dry, a baler can be employed to pack them into bales, if desired, for long-term storage.
Haying is a labor and capital intensive endeavor. As explained above, several different operations are usually necessary before the hay is ready for storage. Each of these operations usually involves an operator passing crop processing equipment through the field. Increasing the speed and efficiency at which these operations are performed reduces the amount of equipment and labor necessary to perform these operations. Since the maximum speed at which the crop processing equipment passes through the field to process the crops is usually limited by the design of the equipment and the terrain of the field, the best way to increase the speed and efficiency of the crop processing equipment is to increase the working width of the equipment, which increases the width of the swath of field processed with each pass.
In haying, increasing the working width of a hay rake minimizes the number of passes through a field necessary to perform a raking or an over-turning operation. If the hay rake is used to gather multiple windrows into a single windrow, then the increase in speed and efficiency, due to the rake""s increased working width, can extend also to other equipment which performs previous and subsequent operations on the field. For example, if a hay rake is used to gather two windrows into a single windrow, then an increase in the working width of the hay rake permits a corresponding increase in the distance between the windrows, and thus a corresponding increase in the working width of the windrower and a resultant increase in the speed and efficiency of the windrower. As another example, if two windrows are gathered into a single windrow by a hay rake, then the number of passes necessary for a baler to later gather the crop from the windrows and into bales can be reduced (because there are fewer windrows) resulting in an increase in speed and efficiency of the baler.
As is shown by the above discussion of haying, it is advantageous to use the widest possible haying equipment. For other purposes as well, such as for the processing of bean crops before harvesting, and other operations in the agricultural and construction fields, it is advantageous to use the widest possible processing equipment. There is, thus, a substantial need for such equipment.
Several factors have limited the maximum working width of positionable work implements. One factor is the method of transportation of the equipment from field to field. The positionable work implement must generally be transported on roads shared with other traffic. The positionable work implement must therefore be capable of configuration for road transport to a certain maximum width, i.e., a width which safely allows opposing traffic to pass on the road.
U.S. Pat. No. 4,343,142, partially addressed the above-mentioned limitation to the maximum working width of positionable work implements. The ""142 patent discloses a positionable work implement with a main frame wherein sections of the frame transverse to the direction of travel are telescopically received within other sections. Two implement assemblies pivotally attach to the main frame at the ends of these telescoping transverse sections. Before travelling on a road, the transverse width of the main frame may be reduced by telescopically retracting the sections of the main frame within one another. For operation of the work implements in a field, the main frame may be telescopically extended in a transverse direction, thereby increasing the width of the main frame and the working width of the positionable work implement.
Despite the use of this type of telescopic adjustment of a positionable work implement, the maximum working width of a positionable work implement is still limited to at most three times the width of the main frame in its narrowest configuration, due to mechanical constraints. More specifically, the length of the telescoping sections generally cannot be greater than the width of the main frame, without compromising the structural integrity of the frame.
The primary object of the present invention is to provide a positionable work implement with a wider working width than was previously possible while still allowing the positionable work implement to be configured for safe transport on a road.
In one embodiment according to the present invention, a positionable work implement has a pivotally adjustable frame to permit rotational adjustment of the frame about a vertical axis. The apparatus includes a main frame provided with a transverse frame section, upon which at least one work implement is mounted. The apparatus also includes a connection assembly for pivoting the transverse frame section about a vertical axis. The apparatus also has at least one ground traversing element pivotally mounted on the main frame for movement about a vertical axis such that the ground traversing element may be oriented substantially parallel to the direction of travel for any orientation of the transverse frame section. In operation, the transverse frame section may be pivoted about a vertical axis to an orientation in which its effective transverse width is reduced to facilitate transport, and pivoted about a vertical axis to another orientation in which its effective transverse width is maximized to deploy the work implements in the widest possible configuration to increase speed and efficiency.
In another embodiment, the present invention provides work implements having a greater effective width. Such work implements include an additional device for supporting rake tine bars to thereby overcome the mechanical constraints on the width of the work implements.
The first and second embodiments may be combined in any suitable manner to further maximize the effective working width of a positionable work implement.